Impossible to change the texture

Hello,

I would like to change the texture of the dummy which is spawned during splinter explosions. It is in data\Library\Materials at the end of the file : DMY_ZB.

I imported new textures but it doesn't change anything in game. I searched for an external texture but didn't find any. Then, I disabled "enable explicit texture" and the dummy was white in game ....

Help please !